Police officers (top R) patrol the Parque Alegria slum as a military helicopter flies overhead during an operation to install the Police Peacekeeping Unit (UPP) in the region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP) 

Police officers take up position at the Parque Alegria slum during an operation to install the Police Peacekeeping Unit (UPP) in the region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP) 

A Brazilian marine stands in front a combat car before an operation to install the Police Peacekeeping Unit (UPP) in the Parque Alegria slum and its region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP MILITARY) 

Brazilian marines inside a combat car observe as police officers from the Special Operations Battalion (BOPE) stand before an operation to install the Police Peacekeeping Unit (UPP) at Parque Alegria slum and its region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP MILITARY) 

Police officers walk on a railroad as they patrol the Parque Alegria slum during an operation to install the Police Peacekeeping Unit (UPP) in the region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP) 

A police officer patrols the Parque Alegria slum during an operation to install the Police Peacekeeping Unit (UPP) in the region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP) 

Police officers patrol the Parque Alegria slum as their colleagues (L) patrol the Linha Vermelha freeway, a major access route to Rio de Janeiro's International Airport, during an operation to install the Police Peacekeeping Unit (UPP) in the region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP) 

A resident opens the door for a police officer as he patrols the Parque Alegria slum during an operation to install the Police Peacekeeping Unit (UPP) in the region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP) 

Brazilian marines drive a combat car next to the Linha Vermelha freeway, which is the major access route to Rio de Janeiro's International Airport, during an operation to install the Police Peacekeeping Unit (UPP) at Parque Alegria slum and its region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP MILITARY) 

Brazilian marines drive a combat car next to the Linha Vermelha freeway, which is the major access route to Rio de Janeiro's International Airport, during an operation to install the Police Peacekeeping Unit (UPP) at Parque Alegria slum and its region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP MILITARY) 

A police officer patrols the Parque Alegria slum during an operation to install the Police Peacekeeping Unit (UPP) in the region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP) 

Police officers walk on a railroad during a patrol at the Parque Alegria slum as residents talk at a street bar during an operation to install the Police Peacekeeping Unit (UPP) in the region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST) 

Police officers take up position at the Parque Alegria slum during an operation to install the Police Peacekeeping Unit (UPP) in the region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP) 

Police officers patrol the Parque Alegria slum during an operation to install the Police Peacekeeping Unit (UPP) in the region, in Rio de Janeiro March 3, 2013. The introduction of the peacekeeping program in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. REUTERS/Ricardo Moraes (BRAZIL - Tags: CRIME LAW CIVIL UNREST SPORT SOCCER WORLD CUP)